From NTWind Software:
Visual Subst is a small enhancement utility which allows you create virtual drive letters to the most accessed directories in your system. For example, a long path C:\Documents and Sttings\User\My Documents\Projects\ could be easily accessed via the drive letter P: from any application. It may be very useful when working with deep folder hierarchies as well as when working with projects copied from another system.
What's new in this version:
Fixed an error message if drive letter is used by another program.
Small, Easy to use graphical interface, Can use with folders that cannot be "subst"ed in dos because of their long name.
It fulfils all of my virtual mapping needs.
None found yet.
You can create "virtual" drives that point to a folder but appear as a drive in windows explorer. This is analogous to the dos program SUBST which does the same thing but Virtual Subst can work with folders that have names that are too big to access in dos, or have spaces, or do not have an assigned 8 character dos name (remember that SUBST was created in the dark times where file and folder names had to be less than 8 characters long and where dinosaurs roamed the earth!).
I use this program to create virtual drives from folders that contain DVD files for Mediaplayer classic to open as a DVD. I know what you're about to say, this guy is a tool because you can just make an iso and mount it instead, well yes but I like doing it my way :-P